How to define Nebulae in SSC file

[rian4me]

Is there a way to define a class Nebula in a SSC file
I know you can put a nebula around a star using the SSC but do you really need DSC always to define nebula.

My problem is that i have lot of Nebulae addons installed which all come with the DSC files and these get loaded on startup
thus hogging memory and slowing celestia down, if its an SSC it will load only when needed right?

SO is there any bypass for this..to keep the nebulae..yet not to have them auto loaded at startup.

Also please tell me if there are any addons for rendering better quality Milky way with labeled arms.

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Celestia 1.6.0
Win XP SP2
1.5 GB Ram
2.66Ghz Intel Dual Core

[selden]

All models and textures are loaded into memory the first time they come into view. If they're behind the viewpoint, they don't get loaded.

SSC models and textures can be preloaded, but DSC cannot.
Objects in SSC files are not drawn if the viewpoint is more than a few LY from the star.

[rian4me]

Thanks,

But are you saying that having too many nebulae in my extras folder is not the reason why celestia is slowing down
I tried with and without my big nebulae folder and the difference in rendering of objects waS quite significant..especially wen looking at the milky way from whole galaxy perspective and then trying to move it about the screen..It was much easier on my processor to move the Milky way without my nebulae folder, even though i had not visited a single nebula.

What could then be the reason for this..any idea?

[Cham]

The best way is to define the nebula as an invisible layer, that you turn ON/OFF with a CELX toggle script. This is the systematic way I adopted, and I now have TONS of large hires nebulae in my Celestia universe, without any impact on the frame rate. I made a special sub-menu, in the scripts menu, just for the nebulae. For many examples, just check the nebulae that I published there :

viewtopic.php?f=23&t=15543

[fsgregs]

Cham's method is good but there are other ways around this if you don't know how to write toggle scripts. The Milky Way is defined as a galaxy, so you can turn Nebula off as the default setting when Celestia first loads. The Milky Way and all galaxies will still load.

To load Celestia without nebula being active, simply uncheck the nebula box in the Render menu, then close Celestia. When you reopen it, the program should remember that nebula was unchecked, and it will not load any nebula extras.

You can also be certain that nebula do not load on startup by instructing Celestia not to turn on nebula when it boots, by adding one line to the "start.cel" file in the Celestia root folder. To do so, right-click on that file and "open with" Wordpad, or some other text editor. Once the file is open, locate the text section that says,

# Items to be displayed (rendered):
# Do NOT render the following objects (UNcomment to suit your needs)...
# renderflags {clear "atmospheres"}
# renderflags {clear "automag"}
# renderflags {clear "boundaries"}
# renderflags {clear "cloudmaps"}
# renderflags {clear "comettails"}

Add this line to that section:
renderflags {clear "nebulae"}

Save the file.

Then, Celestia will never boot up with nebula active, until you turn nebula on with the render menu.

A third way to do this is to separate your nebula files into two extras folders. One folder contains the nebula you do want to see, and the other contains the nebula you do not want to see. Call it "extras2".

When you want to see both sets of those nebula, simply edit one line in the "celestia.cfg" file that you can find in the main directory. That line is:

ExtrasDirectories [ "extras" ]

Change it to ExtrasDirectories [ "extras" "extras2"], save the file, and Celestia will load up both extras folders when it boots. A simple way to do this fast, is to have both lines in the config file, and simply comment out the line you want. For example,

#ExtrasDirectories [ "extras" ]
ExtrasDirectories [ "extras" "extras2"]

Hope this helps

Frank